Article
Geosciences, Multidisciplinary
T. Barreyre, R. Parnell-Turner, J. -N. Wu, D. J. Fornari
Summary: This study indirectly measures the changes in sub-seafloor crustal permeability based on the tidal response of high-temperature hydrothermal vents. The research finds that magmatic intrusion and volcanic eruption can cause abrupt changes in crustal permeability, which greatly influence hydrothermal circulation processes.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geochemistry & Geophysics
Pu Sun, Yaoling Niu, Shuo Chen, Pengyuan Guo, Meng Duan, Yanhong Chen, Hongmei Gong, Yuanyuan Xiao, Xiaohong Wang
Summary: Copper isotope fractionation during magmatic processes has been observed for the first time, with significant fractionation occurring during magma differentiation. The study also found that the fractionation of copper isotopes in magma differentiation is influenced by the redox state and sulfide segregation.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Geochemistry & Geophysics
Natalia Berrios-Rivera, Jeffrey S. Gee, Ross Parnell-Turner, Sarah Maher, Jyun-Nai Wu, Daniel Fornari, Maurice Tivey, Milena Marjanovic, Thibaut Barreyre, Jill McDermott
Summary: By analyzing magnetic anomaly data near 9 degrees 50'N on the East Pacific Rise, researchers have discovered a continuous axial anomaly low, which is likely caused by variations in Earth's geomagnetic field intensity.
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2023)
Article
Geosciences, Multidisciplinary
Robert A. Dunn
Summary: A new two-dimensional tomographic image of the East Pacific Rise at 9 degrees N was created using data from three co-located wide-angle ocean-bottom seismograph experiments. The upper and lower half of the crustal magmatic system show different seismic structures and melt distributions. The system's shape suggests steeper isotherms and stronger hydrothermal circulation in the upper gabbroic section, with relatively flatter isotherms and weaker circulation in the lower gabbroic section.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Multidisciplinary Sciences
Jill M. McDermott, Ross Parnell-Turner, Thibaut Barreyre, Santiago Herrera, Connor C. Downing, Nicole C. Pittoors, Kelden Pehr, Samuel A. Vohsen, William S. Dowd, Jyun-Nai Wu, Milena Marjanovic, Daniel J. Fornari
Summary: Comprehensive knowledge of the distribution and characteristics of off-axis hydrothermal vent fields is crucial for understanding global chemical and heat fluxes, as well as the distribution of endemic fauna. However, current knowledge is biased towards on-axis surveys, and a lack of high-resolution bathymetric surveys in off-axis regions limits the identification of vent fields, potentially leading to an underestimation of the number of vents. This study presents the discovery of an active, high-temperature off-axis vent field, which may have greater stability in fluid composition compared to on-axis vents and suggests that high-temperature convective circulation cells extend further off-axis than previously realized.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Geochemistry & Geophysics
Jyun-Nai Wu, Ross Parnell-Turner, Daniel J. Fornari, Gregory Kurras, Natalia Berrios-Rivera, Thibaut Barreyre, Jill M. McDermott
Summary: Due to the lengthy eruption cycles and remote location of mid-ocean ridges, it is challenging to directly observe seafloor volcanic eruptions. In this study, researchers collected near-bottom data and combined them with other measurements to analyze the volcanic eruptions at 9°50'N on the East Pacific Rise in 2005-2006. The results provided estimations of the lava flow extent and volume, serving as important references for studying future eruptions in the area.
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2022)
Article
Geochemistry & Geophysics
Jyun-Nai Wu, Ross Parnell-Turner, Daniel J. Fornari, Natalia Berrios-Rivera, Thibaut Barreyre, Jill M. McDermott
Summary: Fissures and faults in the crust help us understand how plate separation is accommodated by magma and brittle deformation. In a study of the East Pacific Rise, bathymetric data collected by autonomous underwater vehicles and remotely operated vehicles were used to map these features. The findings suggest that faulting plays a minimal role in plate separation compared to dike intrusion causing open cracks. The study also reveals the importance of reactivation of fissures during volcanic eruptions and provides insights into magma dynamics.
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2023)
Article
Geosciences, Multidisciplinary
Jianhua Gong, Wenyuan Fan, Ross Parnell-Turner
Summary: This study investigates the unique Quebrada system, a multi-strand RTF system on the East Pacific Rise. Through seismic observations and analysis, it reveals the complex seismic activity and possible heterogeneous rotations within the Quebrada system. The evolution of multi-strand RTFs is possibly influenced by strong local thermal and fluid effects, while the RTFs may regulate regional tectonics and form an intricate feedback system.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Oceanography
Sheng Chen, Chunhui Tao, Christopher R. German
Summary: This study tested for both high and low-temperature venting along the equatorial East Pacific Rise and found that low-temperature venting should be widespread along all fast-spreading mid-ocean ridges. The results also suggest that low-temperature fluid flow, out of geochemical equilibrium with the overlying water column, may play an important role in global-scale ocean biogeochemical cycles.
DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS
(2021)
Article
Geology
Ryan A. Portner, Brian M. Dreyer, David A. Clague
Summary: The research aims to explore the eruption characteristics of deep-sea mid-ocean ridges, study the dynamics of magma ascent and gas release, and compare the different volcanic compositions at various depths on mid-ocean ridges. The study found that most eruptions along mid-ocean ridges are nonexplosive in nature.
Article
Geochemistry & Geophysics
Xiao-Yun Nan, Fei Wu, Hui-Min Yu, Jin-Ting Kang, Yong-Jun Gao, Fang Huang
Summary: This study investigates the behavior of barium isotopes during low-temperature seawater alteration and high-temperature hydrothermal alteration processes in the oceanic crust. The results show that the barium isotope compositions of the volcanic section and sheeted dike complex have large variations, possibly due to modification by seawater and hydrothermal fluid. The samples from the plutonic complex display lighter barium isotope compositions, reflecting the influence of late magmatic fluids. The recycling of the altered oceanic crust could result in barium isotope heterogeneity in the mantle.
Article
Geochemistry & Geophysics
David B. Rowley, Alessandro M. Forte
Summary: Discrepancies are found between predicted and observed plate motion histories, and the influence of deep mantle buoyancy on plate motions is proposed.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Geochemistry & Geophysics
Tianze Liu, Jianhua Gong, Wenyuan Fan, Guoqing Lin
Summary: Ocean transform faults can generate characteristic earthquakes on a regular basis, and the Gofar transform fault in the Western Ocean experiences similar M6 earthquakes every 5 years. Microseismicity suggests that the fault is divided into five distinct zones, including a rupture barrier zone that may affect adjacent earthquakes. The role of pore fluids in regulating the slip behavior of the fault is still unknown.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Agriculture, Multidisciplinary
Chunhua Zhu, Yayu Chen, Michail N. Isupov, Jennifer A. Littlechild, Lifang Sun, Xiaodong Liu, Qianchao Wang, Hui Gong, Panpan Dong, Na Zhang, Yunkun Wu
Summary: The crystal structure of an esterase, EprEst, from deep-sea hydrothermal vent was reported, showing a unique spatial arrangement and substrate preference. Molecular docking analysis revealed the active site pocket's capability to accommodate ligands of varying lengths. Semi-rational design successfully improved the thermostability and enzyme activity of EprEst.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2021)
Article
Multidisciplinary Sciences
Ajit Kumar Patra, Maeva Perez, Sook-Jin Jang, Yong-Jin Won
Summary: The mytilid mussel Bathymodiolus thermophilus is able to live in deep-sea hydrothermal vent regions due to its symbiotic relationship with chemosynthetic bacteria. This study shows that these symbionts can have different gene compositions, allowing them to utilize different chemicals in the environment. It also reveals that B. thermophilus can associate with multiple symbiont strains, which may help them colonize various chemosynthetic environments across the global oceans.
SCIENTIFIC REPORTS
(2022)
Article
Geochemistry & Geophysics
Marzia Miletto, Xiangli Wang, Noah J. Planavsky, George W. Luther, Timothy W. Lyons, Bradley M. Tebo
Summary: Stable chromium isotopes have been used as a paleoredox proxy to track atmospheric oxygenation, with previous belief that Cr oxidation is limited to terrestrial settings. However, recent research shows rapid marine Cr(III) oxidation linked to microbial Mn(II) oxidation, challenging the traditional view. Initial partial oxidation of Cr(III) to Cr(VI) can cause a small isotope fractionation, calling for a reevaluation of the link between Cr isotope values and atmospheric oxygenation.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2021)
Article
Geochemistry & Geophysics
Minming Cui, George W. Luther, Maya Gomes
Summary: Research on the concentration patterns of redox-sensitive trace metals tungsten and molybdenum in aquatic environments to track changes in sulfidic conditions in ancient aquatic environments. Through experiments and analysis, the correlation between the two was discovered, providing a new framework for using these trace metals to track ancient redox conditions.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2021)
Article
Geochemistry & Geophysics
George W. Luther III, Jennifer S. Karolewski, Kevin M. Sutherland, Colleen M. Hansel, Scott D. Wankel
Summary: Recent studies have revealed the potential interaction between Mn and nitrogen species, shedding light on the abiotic oxidation mechanism of nitrite by Mn(III)-pyrophosphate under environmentally relevant conditions. The reaction involves two one-electron transfer steps and shows that nitrous acid serves as the reductant in the process, leading to the formation of nitrate as the end-product. This work provides a mechanistic perspective on the important relationship between Mn and nitrogen in environmental settings.
AQUATIC GEOCHEMISTRY
(2021)
Article
Oceanography
Coral Diaz-Recio Lorenzo, Daisy ter Bruggen, George W. Luther, Amy Gartman, Sabine Gollner
Summary: The study investigated the abundance and diversity of copepods associated with foundation species in different physiochemical environments at the active vent site ABE, finding that species richness and Shannon diversity were significantly higher in the Bathymodiolus habitat with lower temperatures, sulfur concentrations, and higher oxygen levels, driven by a community comprised mostly of habitat generalists.
DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS
(2021)
Article
Engineering, Environmental
Nanqing Zhou, George W. Luther, Clara S. Chan
Summary: This study quantified biotic and abiotic Fe(II) oxidation rates using a model microaerophilic Fe(II)-oxidizing bacterium in the presence of different organic ligands. Results showed that various models and natural iron-binding ligands have distinct effects on abiotic versus biotic Fe(II) oxidation rates. Organic ligands such as citrate and NTA were found to have different effects on the oxidation rates.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Editorial Material
Geosciences, Multidisciplinary
George W. Luther
Summary: Based on the C-14 data, the study confirms that dissolved organic carbon (DOC) in the deep ocean is over 6,000 years old and primarily originates from seawater passing through the ocean crust and expelling from hydrothermal vents. However, the chemical composition of this refractory DOC remains unknown, requiring collective efforts from the marine organic chemistry community to elucidate it.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Chemistry, Multidisciplinary
George W. Luther, Katherine M. Mullaugh, Emily J. Hauser, Kevin J. Rader, Dominic M. Di Toro
Summary: The study discusses the dissolved chemical speciation of metals in natural waters and methods to investigate metal organic ligand complexes. Competitive ligand exchange-cathodic stripping voltammetry titrations and pseudovoltammetry provide information about metal-ligand complexes. Kinetic experiments combined with the addition of competitive ligands offer insights into the dissociation rate constant and conditional equilibrium constant of the unknown metal-ligand complexes.
Article
Geochemistry & Geophysics
Khoren Avetisyan, Irina Zweig, George W. Luther, Alexey Kamyshny Jr
Summary: This study investigated the formation rates of hydrogen sulfide oxidation products by delta-MnO2 under environmentally-relevant conditions, revealing the distribution characteristics of specific sulfur states in the initial stage of polysulfides formation.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2021)
Article
Chemistry, Multidisciplinary
Emily R. Estes, Debora Berti, Alyssa J. Findlay, Michael F. Hochella, Timothy J. Shaw, Mustafa Yucel, Eric H. De Carlo, George W. Luther
Summary: Extensive sampling at the East Pacific Rise hydrothermal vent field showed that mixing of vent fluid with seawater results in the formation of nanoparticulate phases and the rapid precipitation/aggregation of metal sulfide minerals. Iron speciation and transport is decoupled from that of copper and zinc. Zinc and copper sulfide phases form nano-sized particles that can be easily removed by filtration, while iron sulfides exist as larger particles. Formation of pyrite nanoparticles is influenced by physical mixing and temperature. pH and zero point of charge of metal sulfides control particle formation and aggregation. Trace metal concentrations vary between vent sites, highlighting the importance of diffuse flow systems in hydrothermal metal emissions. The behavioral differences near the vents have implications for long-distance transport of metals.
ACS EARTH AND SPACE CHEMISTRY
(2022)
Article
Engineering, Environmental
Jeffrey M. Hudson, George W. Luther, Yu-Ping Chin
Summary: This study used mediated electrochemical oxidation to directly measure the extent of Fe(II) oxidation in the presence of different organic ligands, and obtained the apparent standard redox potentials and stability constant ratios of Fe(III)/Fe(II). The experimental results showed that different ligands had different effects on the reactivity of Fe(II), which is of great significance for understanding the role of Fe(II) in biogeochemical processes and contaminant attenuation.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Engineering, Environmental
Ke Wen, Oliver A. Chadwick, Peter M. Vitousek, Elizabeth L. Paulus, Gautier Landrot, Ryan V. Tappero, John P. Kaszuba, George W. Luther, Zimeng Wang, Benjamin J. Reinhart, Mengqiang Zhu
Summary: Manganese oxidation states in highly weathered volcanic soils in Hawaii were studied across two rainfall gradients. It was found that as the mean annual precipitation increased, the soil redox conditions shifted from oxic to suboxic and to anoxic, resulting in decreased proportions of Mn(IV) and increased proportions of Mn(II). Mn(III), on the other hand, accumulated in soils with prevalent suboxic conditions at intermediate precipitation levels. The soil redox conditions and rainfall-driven leaching jointly controlled the concentration of exchangeable Mn(II) in soils.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Marine & Freshwater Biology
S. Fisher Gonski, William J. Ullman, D. Tye Pettay, Karl S. Booksh, Todd R. Martz, George W. Luther, Wei-Jun Cai
Summary: This study assessed the performance of Durafet-based sensors in estuarine waters and found dynamic errors in the temperature and salinity responses of the internal and external reference electrodes. The errors were primarily driven by tidal mixing and were corrected using a dynamic sensor response correction method. The results showed that salinity change was the strongest limiting factor for the reference electrode response.
ESTUARINE COASTAL AND SHELF SCIENCE
(2023)
Article
Limnology
Aubin Thibault de Chanvalon, George W. W. Luther, Veronique E. Oldham, Bradley M. M. Tebo, Nicole R. R. Coffey, Timothy F. F. Shaw
Summary: We conducted a study in the Pacific Ocean at the East Pacific Rise to investigate the distribution of dissolved Mn from the surface to the hydrothermal vents. We found that dissolved Mn(III) bound to humic acid accounted for a significant portion of the total dissolved Mn, especially in the hydrothermal plume and at the redox boundaries. The stability and temporal variability of Mn(III)-humic acid highlight the importance of non-steady-state processes in the open ocean.
LIMNOLOGY AND OCEANOGRAPHY
(2023)
Review
Environmental Sciences
George W. W. Luther III
Summary: The transformation between iodate and iodide has attracted a lot of attention due to their dependency on oxygen concentration, which varies in the ocean. Reducing iodate to iodide is the controlling step in the reduction reaction sequence, while oxidizing iodide to iodate is the controlling step in the oxidation process. The reduction of iodate is more favorable than the reduction of nitrate at oceanic pH values, suggesting different reductants can affect the transformation.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Ecology
Aubin Thibault de Chanvalon, George W. Luther, Emily R. Estes, Jennifer Necker, Bradley M. Tebo, Jianzhong Su, Wei-Jun Cai
Summary: This study investigates the carbonate dynamics in the temperate Chesapeake Bay estuary during two summers. The results show that under oxygen-rich conditions, carbonate dissolution, primary production, and aerobic respiration explain the evolution of alkalinity versus dissolved inorganic carbon. In oxygen-depleted waters, a previously unreported increase in dissolved inorganic carbon per alkalinity production was observed, suggesting the involvement of Mn in the carbonate signature.
Article
Oceanography
Jason A. Law, Robert H. Weisberg, Yonggang Liu, Dennis A. Mayer, Jeffrey C. Donovan
Summary: Time series data from a moored array of sensors are used to describe the long-term mean circulation and seasonal variations on the West Florida Continental Shelf. The observations reveal a coherent shelf-wide circulation pattern with alongshore and down-coast flow, and a coastal jet separating an upwelling region from a downwelling region influenced by the deeper ocean.
DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY
(2024)
